The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Referring now to FIG. 1, a functional block diagram of an engine 102 and exhaust system 106 for a vehicle is presented. The engine 102 combusts a mixture of air and diesel fuel to produce torque. The resulting exhaust gas is expelled from the engine 102 into the exhaust system 106. The exhaust system 106 includes an exhaust manifold 108, a diesel oxidation catalyst (DOC) 110, a reductant injector 112, a mixer 114, and a diesel particulate filter (DPF) assembly 116.
The exhaust gas flows from the engine 102 through the exhaust manifold 108 to the DOC 110. The DOC 110 oxidizes particulate unburned hydrocarbon in the exhaust gas as the exhaust gas flows through the DOC 110. The reductant injector 112 may inject a reductant, such as ammonia or urea, into the exhaust system 106. The mixer 114, which may be implemented as a baffle, agitates the exhaust gas and the injected reductant.
The DPF assembly 116 filters particulate from the exhaust gas passing through it. This particulate may accumulate within the DPF assembly 116 and may restrict the flow of exhaust gas through the DPF assembly 116. The particulate may be removed from the DPF assembly 116 by a process called regeneration. A heater assembly 118 may be used to initiate the regeneration process.